The deliverance from sin is still further expressed by that third supplication, 'Cleanse me from my sin.' That is the technical word for the priestly act of declaring ceremonial cleanness--the cessation of ceremonial pollution, and for the other priestly act of making, as well as declaring, clean from the stains of leprosy. And with allusion to both of these uses, the Psalmist employs it here. That is to say, he thinks of his guilt not only as a blotted past record which he has written, not only as a garment spotted by the flesh which his spirit wears, but he thinks of it too as inhering in himself, as a leprosy and disease of his own personal nature. He thinks of it as being, like that, incurable, fatal, twin sister to and precursor of death; and he thinks of it as capable of being cleansed only by a sacerdotal act, only by the great High Priest and by His finger being laid upon it. And we know who it was that--when the leper, whom no man in Israel was allowed to touch on pain of uncleanness, came to His feet--put out His hand in triumphant consciousness of power, and touched him, and said, 'I _will_! be thou clean.' Let this be thy prayer, 'Cleanse me from my sin'; and Christ will answer, 'Thy leprosy hath departed from thee.' III. These petitions likewise show us whence the Psalmist draws his confidence for such a prayer. 'According to the multitude of Thy tender mercies, blot out my transgressions.' His whole hope rests upon God's own character, as revealed in the endless continuance of His acts of love. He knows the number and the greatness of his sins, and the very depth of his consciousness of sin helps him to a corresponding greatness in his apprehension of God's mercy. As he says in another of his psalms, 'Innumerable evils have compassed me about; they are more than the hairs of my head.... Many, O Lord my God! are Thy wonderful works.... They are more than can be numbered.' This is the blessedness of all true penitence, that the more profoundly it feels its own sore need and great sinfulness, in that very proportion does it recognise the yet greater mercy and all-sufficient grace of our loving God, and from the lowest depths beholds the stars in the sky, which they who dwell amid the surface-brightness of the noonday cannot discern.